Experts testify as to cause of death for Derek Williams in day two of inquest

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MILWAUKEE (WITI) -- Tuesday, February 12th was Day Two in the inquest into the death of Derek Williams.

22-year-old Williams died in the backseat of a squad car in July of 2011 after he was picked up by Milwaukee police officers following a foot chase — suspected of an attempted robbery. Williams’ death was captured on a squad camera as he struggled to breathe for nearly 15 minutes without help.

Williams’ death sparked outrage in the community after the dashcam video showing him struggling to breathe was released.

Milwaukee Police Chief Ed Flynn has acknowledged his officers didn’t appropriately respond to Williams before his death. However, Flynn said MPD has changed police procedures to make sure this doesn’t happen again.

A Medical Examiner’s report originally indicated Williams’ cause of death as complications due to Sickle cell trait — but that report was amended, and the cause of death changed to homicide (death at the hands of another).

Now, the question for an inquest jury to answer is what caused Williams' death, and whether anyone is at fault.

On Tuesday, experts said Williams died from what is called a Sickle cell crisis. Experts said Williams had a trait which caused his blood cells to become misshapen -- something that can happen for a number of reasons.

On a July 2011 night, Williams collapsed in the back of a Milwaukee police squad car after police say they chased him as a robbery suspect.

An autopsy showed Williams had a blood disease which caused his blood cells to sickle, and his blood no longer flowed properly through his organs. The doctor who wrote up the autopsy report ruled the death natural.

A year later, Williams cause of death was changed when it was brought to the doctor's attention there was also a police struggle during the arrest.

"I can't say whether the chase alone would have done it -- if it wouldn't have occurred if not for the struggle," Medical Examiner Christopher Poulos said.

Dr. Poulos told the jury he changed his findings from natural causes to homicide, which means there was another person, such as a police officer, involved in Williams' death.

The Milwaukee County Medical Examiner says there could have been a third factor that contributed to Williams going into Sickle cell crisis: the joker mask police say Williams wore when he attempted to rob two college students before they chased him.

"I don't know how long he had it on, but based on the small holes for breathing it would have been a factor when he had it on," Medical Examiner Brian Peterson said.

It was previously thought a bone in Williams' neck had been broken during the struggle, which would have possibly affected his breathing. Now, experts say that bone was never broken, and that was not the cause of his death.

Eventually, the inquest jury will have to give its opinion if anyone was responsible for the death.